Syntax

Prepented +plus and -minus, indicating that the labeled entity should be either required or forbidden -- be it a single word, a phrase, or a parenthetical group.

Logical groups, delimited by parentheses.

Phrases, delimited by double quotes.

Field-specific terms, in the form of fieldname:termtext. For example type:xml typedoc:article

A field can also be given to a logical group, in which case it is the same as if the field had been prepended onto every term in the group. For example: type:(xml html) is the same as type:xml type:html.